Do I Smell a Terpene?

Aaron Rowe over at the WIRED Science blog forwarded me an article that he wrote about research into the chemicals responsible for the spicy aromas associated with noble hops and I thought it worth sharing.  It includes a couple of complex chemical names, but the article itself is very easy to read.  So don't freak out if you are not versed in the complexities of organic chemistry and analytical methods.  Still a little worried?  Here's a quick cliff notes version:

Researchers in Australia and New Zealand used a complex analytical method to separate all of the chemicals found in hops and then asked evaluators to match what they smelled against a list of descriptors.  According to the author, a similar method has been used in the evaluation of wine, coffee, and even manure (I hope they paid them well for that one!)  Just think of it as smelling hops one chemical at a time to figure out exactly what chemical causes fruit vs. floral vs. spicy aromas.  Turns out 5 different chemicals stood out from the others and they all happened to be from the same class of chemicals, terpenes.  Where was this experiment when I was in college doing one of what felt like hundreds of labs?!?!?  I guarantee I never did one anywhere close to "What does my beer smell like?"  Although a few were probably sub-titled "Written while drinking beer".

So what does this mean for brewing?  An area to focus on for producing new hop varieties most likely.  Many of the hop varieties used today are genetic mutations of previously used varieties.  Scientist may now be able to modify a hop variety to increase or decrease the production of a particular terpene.  In doing so, a brewer will be able to better control the aroma of a finished beer by using this new hop.  So don't go adding pine sap to your brew just yet (its high in terpenes)!  I'd wait and leave the terpene modifications to the real professionals.  And please, no matter how tempting, do not even think about using words like Eugeneol and Beta-ionone to describe the aroma on a beer. (Yes...someone out there will do it at some point.  Absolutely tragic!)